This invention relates to compositions and methods useful in disinfecting contact lenses and in preserving contact lens care products. More particularly, the invention relates to compositions and methods in which contact lenses are disinfected and/or contact lens care products are preserved using compositions containing chlorite components and polyanionic components.
The use of chlorine dioxide dissolved in an aqueous liquid medium to disinfect contact lenses has previously been suggested.
Park et al U.S. Pat. No. 5,336,434 and Dziabo et al U.S. Pat. No. 5,338,480 disclose contact lens disinfecting using chlorine dioxide in which delayed release components are used to delay the release of chlorine dioxide activators, chlorine dioxide destroying components and/or cleaning enzyme components. Various delayed release components are disclosed, for example, soluble cellulose ethers such as methylcellulose, methylhydroxypropylcellulose, methylhydroxyethylcellulose, hydroxypropylcellulose, hydroxyethylcellulose and sodium carboxymethylcelluloses; cellulose esters such as cellulose acetate phthalate and hydroxypropylmethyl-cellulose phthalate; polymers derived from at least one of acrylic acid, acrylic acid esters, methacrylic acid and methacrylic acid esters such as methacrylic acid-methyl methacrylate copolymer (for example, that sold by Rohm Pharma under the trademark Eudragit L 100) and methacrylic acid-ethyl acrylate copolymers (for example, that sold by Rohm Pharma under the trademark Eudragit L 30D); polymers derived from methyl vinyl ether and maleic acid anhydride; polyvinylpyrrolidone; polyvinyl alcohols and the like and mixtures thereof. However, neither of these patents discloses that such delayed release components are effective to delay or prevent proteinaceous deposit formation on the contact lens being disinfected or to reduce the toxicity of the disinfecting composition to the human eye.
Dziabo et al U.S. Pat. No. 5,424,078 discloses the use of stabilized chlorine dioxide as a preservative for ophthalmic formulations. Although these preserved formulations provide many benefits, some questions remain about the long term use of stabilized chlorine dioxide in the eye in conjunction with contact lenses. New compositions providing additional and/or enhanced benefits are desirable.
Although polyanionic polymers, such as carboxymethyl cellulose, have been used for rewetting eye drop formulations, for example, to relieve or protect against dry eye irritation, such formulations have been used in single dose product configurations. A multi-dose rewetting eye drop product is highly advantageous, providing convenience, simplicity and low cost to users. However, such a multi-dose formulation has not been provided due to the lack of an adequate, non-cytotoxic and non-irritating preservative for such formulations.
It would be advantageous to provide a new contact lens disinfection system and/or a new contact lens storage system and/or a new preservative system for contact lens care products.